Problem: What do the following two equations represent? $3x+2y = -1$ $-3x-2y = 1$
Solution: Putting the first equation in $y = mx + b$ form gives: $3x+2y = -1$ $2y = -3x-1$ $y = -\dfrac{3}{2}x - \dfrac{1}{2}$ Putting the second equation in $y = mx + b$ form gives: $-3x-2y = 1$ $-2y = 3x+1$ $y = -\dfrac{3}{2}x - \dfrac{1}{2}$ The above equations turn into the same equation, so they represent equal lines.